How to auto import the necessary classes in Android Studio with shortcut?

I've just switch to Android Studio 0.5.1, and the things going so slow here, because nothing works in the regular way...

How do I import the necessary classes with shortcut?

I mean like this ones?

import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.MenuItem;

Go to File -> Settings -> Editor -> Auto Import -> Java and make the below things:

Select Insert imports on paste value to All

Do tick mark on Add unambigious imports on the fly option and "Optimize imports on the fly*

Go on the missing declaration with cursor and press alt+enter

Ctrl + Alt + O to optimize imports

On my Mac Auto import option was not showing it was initially hidden

Android studio ->Preferences->editor->General->Auto Import

and then typed in searched field auto then auto import option appeared. And now auto import option is now always shown as default in Editor->General. hopefully this option will also help others. See attached screenshot

To import classes on the fly :

On OSX press Alt(Option) + Enter.

File -> Settings -> Keymap Change keymaps settings to your previous IDE to which you are familiar with

You can also use Eclipse's keyboard shortcuts: just go on preferences > keymap and choose Eclipse from the drop-down menu. And all your Eclipse shortcuts will be used in here.

On Windows with Android Studio 1.5.1 : File --> Settings --> Editor --> General --> Auto Import